I am considering the purchase of an M&P 22 Compact. When the gun comes from the factory is the rear sight usually adjusted accurately for windage and elevation or is re-adjustment normally required by the shooter?
Accuracy varies with ammo, so your experience may vary.
Prepare several types of ammo, see what functions and groups best, then adjust your sights for that ammo. Or, adjust the sights to whatever ammo you plan on shooting the most.
You need the correct Allen wrench. Check the manual for direction of rotation. Make small adjustments (1/4 to 1/2) and keep track of the direction and number of turns so you can go back if you need to.
You can use a range bag on the bench. I have one of these for sighting in.